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2 arxiv:astro-ph/ v2 19 Aug 2002 TABLE 1 Observing Log IRAS z log( Lir ) Optical Near-Infrared L F SC Date Exp. Seeing Date Exp. Seeing (1) (2) (3) (4) (5) (6) (7) (8) (9) / / / / / / / / / / / / / / / / / / / / / / / / / / /99 a / / / / / / / / / Z / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / /

3 TABLE 1 Continued IRAS z log( Lir ) Optical Near-Infrared L F SC Date Exp. Seeing Date Exp. Seeing (1) (2) (3) (4) (5) (6) (7) (8) (9) / / / / / / / / / / Z / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / /

4 TABLE 1 Continued IRAS z log( Lir ) Optical Near-Infrared L F SC Date Exp. Seeing Date Exp. Seeing (1) (2) (3) (4) (5) (6) (7) (8) (9) / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / a Observed under non-photometric conditions. Col 1: The IRAS object name in the Faint Source Database (FSDB). The prefix FSC is the standard designator for sources in the Faint Source Catalog. The prefix Z is used for objects that are not in the FSC these objects are contained in the Faint Source Reject File (see Moshir et al. 1992). Col 2: Optical redshifts from Kim & Sanders (1998). Col 3: Infrared luminosity calculated using the prescription of Sanders & Mirabel (1996). Col 4: Observing date in Month/Year format. 08/86 (Palomar 60, RCA CCD, 0.47 /pixel), 10/86 (Palomar 60, RCA CCD, 0.47 /pixel), 04/87 (Palomar 60, RCA CCD, 0.47 /pixel), 07/87 (Palomar 60, RCA CCD, 0.47 /pixel), 04/90 (MaunaKea 88, NSF CCD, 0.53 /pixel), 04/91 (MaunaKea 88 GEC CCD, 0.20 /pixel), 06/92 (MaunaKea 88, TEK CCD, 0.22 /pixel), 03/93 (MaunaKea 88, TEK CCD, 0.22 /pixel), 12/93 (Palomar 60, TEK CCD, /pixel), 11/94 (MaunaKea 88, TEK CCD, 0.22 /pixel), 02/95 (MaunaKea 88, TEK CCD, 0.22 /pixel), 08/95 (MaunaKea 88, TEK CCD, 0.22 /pixel), 09/99 (MaunaKea 88, Orbit CCD, 0.07 /pixel), 05/00 (MaunaKea 88, TEK CCD, 0.22 /pixel) Col 5: Exposure time in seconds. Col 6: Seeing in arcseconds. Col 7: Observing date in Month/Year format. 06/92 (MaunaKea 88, NICMOS CCD, /pixel), 02/93 (MaunaKea 88, NICMOS CCD, /pixel), 04/93 (MaunaKea 88, NICMOS CCD, /pixel), 02/95 (MaunaKea 88, QUIRC CCD, /pixel), 08/95 (MaunaKea 88, QUIRC CCD, /pixel), 12/95 (MaunaKea 88, QUIRC CCD, /pixel), 04/96 (MaunaKea 88, QUIRC CCD, /pixel), 12/98 (MaunaKea 88, QUIRC CCD, /pixel), 07/00 (MaunaKea 88, QUIRC CCD, /pixel) Col 8: Exposure time in seconds. Col 9: Seeing in arcseconds. 3

5 Preprint typeset using L A TEX style emulateapj v. 11/12/01 OPTICAL AND NEAR-INFRARED IMAGING OF THE IRAS 1-JY SAMPLE OF ULTRALUMINOUS INFRARED GALAXIES. I. THE ATLAS D.-C. KIM 1,2, S. VEILLEUX 3,5, AND D. B. SANDERS 4,5 arxiv:astro-ph/ v2 19 Aug 2002 ABSTRACT An imaging survey of the IRAS 1-Jy sample of 118 ultraluminous infrared galaxies was conducted at optical (R) and near-infrared (K ) wavelengths using the University of Hawaii 2.2m telescope. The methods of observation and data reduction are described. An R and K atlas of the entire sample is presented along with some of the basic astrometric and photometric parameters derived from these images. A more detailed analysis of these data is presented in a companion paper (Veilleux, Kim, & Sanders 2002). Subject headings: galaxies: active galaxies: interactions galaxies: photometry galaxies: starburst infrared: galaxies 1. INTRODUCTION Ultraluminous infrared galaxies (ULIGs; log [L IR /L ] 12 by definition; H 0 = 75 km s 1 Mpc 1 and q 0 = 0) are an important class of extragalactic objects that appear to be powered by a mixture of starburst and AGN activity, both of which are fueled by an enormous supply of molecular gas that has been funneled into the nuclear region during the merger of gas-rich spirals. ULIGs rival quasi-stellar objects (QSOs) in bolometric luminosity, and there is speculation that ULIGs may indeed represent an important stage in the formation of QSOs as well as powerful radio galaxies, and that they may also represent a primary stage in the formation of giant ellipticals (see Sanders & Mirabel 1996 for a review). A complete sample of 118 ULIGs ( f 60 > 1) was compiled by Kim (1995; see also Kim & Sanders 1998) from a redshift survey of objects in the IRAS Faint Source Catalog (FSC: Moshir et al. 1992). As the nearest (median redshift = 0.145) and brightest ULIGs, this so-called 1-Jy sample provides the best list of objects for detailed multiwavelength studies. Optical spectroscopy for 108 objects in the sample has been published by Veilleux, Kim, & Sanders (1999a), and near-infrared spectra have been published for 60% of the sample by Veilleux, Sanders, & Kim (1999b). We now present the results from our optical and near-infrared ground-based imaging study of this sample. In this first paper, we discuss the methods of observation and data reduction ( 2) and then present an R and K atlas of the 1-Jy sample ( 3.1) along with some of the basic astrometric ( 3.2) and photometric ( 3.3) parameters derived from these images. In Paper II (Veilleux, Kim, & Sanders 2002, we examine the data in more detail and combine the results of the image analysis with those from our spectroscopic survey and other published studies to address the important issue of the origin of ULIGs and their possible evolutionary link with QSOs, radio galaxies, and ellipticals. For both this and the companion papers, we adopt H 0 = 75 km s 1, q 0 = 0.0, MR = 21.2 mag. and MK = 24.1 mag. The values for M are justified in 1 of Paper II. 2. OBSERVATIONS AND DATA REDUCTION 2.1. Optical Imaging Optical images for all 118 ULIGs were obtained at the Cassegrain focus of the University of Hawaii (UH) 2.2m telescope with the Kron-Cousins R filter (6400 Å). These CCD images were bias-subtracted and flat-fielded using normalized dome flat. Bad columns were removed by interpolation using nearby pixel values, and cosmic-rays were removed with the COSMIC package in IRAF. Except for one object, IRAS F , all objects were observed under photometric conditions and have been calibrated with the Landolt standard stars (Landolt 1983, 1992). Atmospheric extinction was corrected using 2 3 observations of the same standard stars at different airmasses through the night. The IRAF task IMALIGN was used to register the images for a given object, and the task IMCOMBINE was used to coadd them together. A summary of our observations is given in Table 1 including object names, redshifts and infrared luminosities, observing dates, exposure times, telescopes and instrument used, pixel scales and seeing estimated from the full widths at half maximum (FWHM) of stellar images within the field of view Near-Infrared Imaging All of the near-infrared images were obtained under photometric conditions with either the NICMOS3 or QUIRC nearinfrared array camera at the Cassegrain focus of the UH 2.2m telescope using a K filter. The central wavelength of the K filter is 2.1µm. It is designed to significantly reduce the thermal background compared to the conventional 2.2µm K filter (Wainscoat & Cowie 1992). The plate scales of the NICMOS3 and QUIRC cameras are pixel 1 and pixel 1, respectively. For observations made prior to April 1993, separate nearby sky frames were obtained by moving the telescope away from the source position, and these sky frames were then combined to produce final median sky frames. For the rest of the observations, sky frames were constructed by median filtering dithered object frames. Because the sky brightness 1 Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 1-87, Nankang, Taipei, 115 Taiwan 2 Current address: School of Earth and Environmental Sciences (BK21), Seoul National University, Seoul, Korea; dckim@astro.snu.ac.kr 3 Department of Astronomy, University of Maryland, College Park, MD 20742; veilleux@astro.umd.edu 4 Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822, and Max-Planck Institut for Extraterrestrische Physik, D-85740, Garching, Germany; sanders@ifa.hawaii.edu 5 Visiting Astronomer, W. M. Keck Observatory, jointly operated by the California Institute of Technology and the University of California 1

6 2 changes rapidly, the median-filtered sky frames were rescaled to the sky values of each object frame before the sky subtraction. Prior to this subtraction, all hot pixels were eliminated from the distribution of pixel values in dark frames. The distribution of pixel values is expected to be Gaussian and if a pixel value lies above or below the 3σ values, then we regarded it as hot. Dome flats were obtained at the beginning and end of each night by turning a lamp in the dome on and off. The darksubtracted flats were obtained by subtracting the lamp-off flats from the lamp-on flats. Flat-fielded images were then coadded after shifting in fractional pixel units with respect to the object center. During this procedure we carefully inspected all of the image frames to see if any hot pixels remained near the target object. Any remaining hot pixels near the target were then replaced with the median value from all other frames at the same position. The final coadded images were calibrated from observations of infrared standard stars (Elias et. al. 1982) using the PHOT or POLYPHOT packages in IRAF. Airmass corrections were carried out using the same procedure as for the optical observations. The near-infrared observations are summarized in Table EMPIRICAL RESULTS 3.1. The Atlas The R and K greyscale images and contour plots of the entire 1-Jy sample of ULIGs are presented in Figure 1. It is immediately evident from this figure that nearly all of the objects in the 1-Jy sample show signs of a strong tidal interaction/merger in the form of distorted or double nuclei, tidal tails, bridges, and overlapping disks. These results are qualitatively consistent with previous imaging surveys of ULIGs (e.g., Sanders et al. 1988; Melnick & Mirabel 1990; Murphy et al. 1996; Clements et al. 1996; although see Lawrence et al. 1989; Zou et al. 1991; Leech et al. 1994). Recent surveys with HST and adaptive optics systems have also confirmed these results (e.g., Surace et al. 1998; Zheng et al. 1999; Scoville et al. 2000; Borne et al. 2000; Cui et al. 2001; Farrah et al. 2001; Colina et al. 2001; Bushouse et al. 2002; Surace & Sanders 1999, 2000; Surace, Sanders, & Evans 2000, 2001). Great care was used to determine which objects in the field are involved in tidal interactions and which ones are not (the description of this analysis is postponed until 3 in Paper II). Faint tidal features and distortions are generally easier to detect in our R-band images. Galaxies labeled G in Figure 1 indicates a nearby group member with no evidence of tidal interaction with the main galaxy. The group membership of these galaxies was individually determined using a series of spectroscopic observations with the Keck II telescope. These observations will be described in Paper II along with the results from a quantitative analysis of the imaging data Astrometry We have measured the positions of the main galactic nuclei from the R and K images. To determine the position of each nucleus, we first retrieved the positions of 3 8 stars around the galaxy from the USNO-A1.0 catalog (Monet et al. 1996). A plate solution was then derived using the IRAF task PLTSOL. The typical positional error ( 2-σ) is estimated to be less than The positions of the nuclei are listed in the second and third columns of Table 2. The median values of the positional offsets between the R and K nuclei is 0. 48, or 1.22 kpc if we convert arcseconds into physical scale. Using the optical spectral types derived from our optical spectroscopy (Veilleux et al. 1999a), we find that the median values of the offsets are (1.3 kpc), (1.2 kpc), (1.3 kpc), and (0.9 kpc) for H II region-like, LINER, Seyfert 2, and Seyfert 1 galaxies, respectively. This marginally significant positional offset can be attributed to the wavelength-dependent effects of dust extinction along our line of sight. The smaller offset among Seyfert 1s may indicate less dust extinction in these objects Aperture photometry Global and nuclear (4-kpc diameter) aperture photometry was performed for each galaxy in the sample. The results of these measurements are listed in Table 3. Since the 1-Jy sources are selected to have b > 30 (Kim & Sanders 1998), the photometry presented in this paper has not been corrected for Galactic extinction. Figure 2 shows the distribution of the integrated (= nuclear + host) R and K absolute magnitudes of our sample galaxies. The absolute magnitudes range from 20.1 to 26.4 at R (mean = 21.9 ± 0.9, median = 21.83) and from 23.7 to 29.3 at K (mean = 25.3 ± 1.1, median = 25.2). Using M R = 21.2 and M K = 24.1 for an L galaxy with H 0 = 75 km s 1 Mpc 1 (see discussion at the end of 1 in Paper II), these magnitudes are equivalent to ( ) L at R (K ), with means and medians around 2 (3) L. Figure 3 shows the distribution of global and nuclear R K colors. The global R K and nuclear (4-kpc diameter) (R K ) 4 colors range from 2.15 to 5.28 and 3.18 to 6.81 with median values of 3.25 and 4.37, respectively. There is a strong correlation between the global and nuclear R K colors (not shown here); this correlation is expected since the nuclear color contributes significantly to the global color. These colors can be compared with those of normal galaxies using the photometric tables of de Vaucouleurs & Longo (1988). In their table, we find 14 galaxies (5 ellipticals, 9 spirals) which have Kron- Cousins R and near-infrared K and H magnitudes; for these objects we find a mean R K value of 2.62 ± The H magnitude was used to convert K to K magnitudes using the conversion formula K = K + (0.22 ± 0.03)(H K) from Wainscoat & Cowie (1992). Dust extinction in the nuclei of ULIGs is at least partially responsible for the redder colors of ULIGs relative to normal galaxies; dust emission at K may also be important in ULIGs. This issue is discussed in more detail in Paper II. We define the compactness of a galaxy as the ratio of nuclear (4-kpc diameter) to total luminosities. Figures 4 shows the histograms of the R and K compactness values. The R (K ) compactness ranges from 0.03 (0.10) to 0.53 (0.91) with a mean value of 0.14±0.09 (0.36±0.17) (1 σ). The ULIGs in our sample are therefore significantly more compact at K than at R, possibly a consequence of the lower extinction and stronger warm-dust emission at longer wavelengths. The dependence of the compactness on the infrared and optical spectroscopic properties of the galaxies will be discussed in Paper II. 4. SUMMARY We have carried out an optical (R) and near-infrared (K ) imaging survey of the IRAS 1-Jy sample of 118 ULIGs. In this first paper, we present an atlas of the sample galaxies and list a few basic astrometric and photometric parameters derived from these images. Nearly all ULIGs show signs of tidal interaction, in agreement with previous studies. The 1-Jy ULIGs show a broad range of luminosities with median R-band (K -band) integrated luminosities of about 2 (3) L. Their nuclear and, to a

7 lesser extent, global R K colors are significantly redder than those of normal galaxies, a result which is attributed to dust reddening and emission in the inner 4 kpc of these galaxies. This is also consistent with the fact that the brightness distributions of 1-Jy ULIGs are more compact at K than at R. The generally smaller nuclear offsets between R and K images among Seyfert 1s may indicate lower dust extinction in these objects, but this result is only marginally significant. A more detailed analysis of these data is presented in a companion paper (Veilleux, Kim, & Sanders 2002; Paper II). 3

8 4 We acknowledge the help from Jim Deane, Aaron Evans, Cathy Ishida, and Joe Jensen in acquiring some of the images presented in this paper. We thank the anonymous referee for a prompt and thorough review. S.V. is grateful for partial support of this research by NASA/LTSA grant NAG D.C.K. acknowledges financial support from the Academia Sinica in Taipei and the BK21 project of the Korean Government. D.B.S. gratefully acknowledges the hospitality of the Max-Planck Institut for Extraterrestriche Physik and is grateful for support from a senior award from the Alexander von Humboldt-Stiftung and from NASA JPL contract This work has made use of NASA s Astrophysics Data System Abstract Service and the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeoronautics and Space Administration.

9 5 REFERENCES Borne, K. D., Bushouse, H., Lucas, R. A., & Colina, L. 2000, ApJ, 529, L77 Bushouse, H. A., et al. 2002, ApJS, 138, 1 Clements, D. L., Sutherland, W. J., McMahon, R. G., & Saunders, W. 1996, MNRAS, 279, 477 Colina, L., et al. 2001, ApJ, 563, 546 Cui, J., Xia, X.-Y., deng, Z.-G., Mao, S., & Zou, Z.-L. 2001, AJ, 122, 63 De Vaucouleurs, A., & Longo, G. 1988, Catalog of optical and infrared photometry of galaxies from 0.5 micrometer to 10 micrometer ( ) (Austin: Univ. of Texas) Farrah, D., et al. 2001, MNRAS, 326, 1333 Kim, D.-C. 1995, Ph.D. Thesis, University of Hawaii Kim, D.-C., & Sanders, D. B. 1998, ApJS, 119, 41 Kim, D.-C., Veilleux, S., & Sanders, D. B. 1998, ApJ, 508, 627 Landolt, A. U. 1983, AJ, 88, 439 Landolt, A. U. 1992, AJ, 104, 340 Lawrence, A., Rowan-Robinson, M., Leech, K., Jones, D. H. P., & Wall, J. V. 1989, MNRAS, 240, 329 Leech, K. J., Rowan-Robinson, M., Lawrence, A., & Hughes, J. D. 1994, MNRAS, 267, 253 Melnick, J., & Mirabel, I. F. 1990, A&A, 231, L19 Monet, D., et al. 1996, USNO-SA1.0, (U.S. Naval Observatory, Washington DC). Moshir, M., et al. 1992, Explanatory Supplement to the IRAS Faint Source Survey, Version 2, JPL D /92 (Pasadena: JPL) (FSC) Murphy, T. W., Jr., et al 1996, AJ, 111, 1025 Sanders, D. B., & Mirabel, I. F. 1996, ARA&A, 34, 725 Sanders, D. B., Soifer, B. T., Elias, J. H., Madore, B. F., Matthews, K., Neugebauer, G., & Scoville, N. Z. 1988, ApJ, 325, 74 Scoville, N. Z., et al. 2000, AJ, 119, 991 Surace, J. A., & Sanders, D. B. 1999, ApJ, 512, 162 Surace, J. A., & Sanders, D. B. 2000, AJ, 120, 604 Surace, J. A., Sanders, D. B., & Evans, A. S. 2000, ApJ, 529, 170 Surace, J. A., Sanders, D. B., & Evans, A. S. 2001, AJ, 122, 2791 Veilleux, S., Kim, D.-C., & Sanders, D. B. 1999a, ApJ, 522, 113 Veilleux, S., Kim, D.-C., & Sanders, D. B. 2002, ApJS, in press (Paper II) Veilleux, S., Sanders, D. B., & Kim, D.-C. 1999b, ApJ, 522, 139 Wainscoat, R. J., & Cowie, L. L. 1992, AJ, 103, 332 Zheng, Z., et al. 1999, A&A, 349, 735 Zou, Z., Xia, X., Deng, Z., & Su, H. 1991, MNRAS, 252, 593

10 6 FIG. 1. R (left) & K (right) greyscale images and contour plots of the 118 objects in the 1-Jy sample of ultraluminous infrared galaxies. Each tick mark represents 5 and the thick vertical bar along the separating line of each pair of panels represents a physical scale of 20 kpc. The bottom contour levels (BCLs) of the R & K images are given in the last two columns of Table 2, and the contour intervals are separated by 0.5 magnitude. Objects labeled G in the figure indicate nearby group members with no evidence of tidal interaction with the main system, and the * symbol indicates a star. The other labels (N, S, E, W, etc) identify the nuclei of parent galaxies and are so labeled in Tables 2 and 3. FIG. 2. R and K absolute magnitudes. These galaxies span a broad range of total (= nuclear + host) luminosities. For comparison, M R = 21.2 and M K = 24.1 for an L galaxy. FIG. 3. Global and nuclear (4-kpc diameter) R K colors. These colors (especially the nuclear values) are considerably redder than those of normal galaxies, < R K >= 2.62±0.34 (1 σ). Dust is the suspected culprit. FIG. 4. R and K compactness values. This quantity is defined as the ratio of the nuclear (4-kpc diameter) to total luminosity. ULIGs are more compact at K than at R, another sign that dust affects the central surface brightnesses of these objects.

11 FIG. 1. 7

12 8 FIG. 2.

13 FIG. 3. 9

14 10 FIG. 4.

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16 TABLE 2 Astrometric and Photometric Parameters IRAS Optical Position (J2000.0) Near-IR Position (J2000.0) BCL F SC R.A. Dec. R.A. Dec. R K (1) (2) (3) (4) (5) arxiv:astro-ph/ v2 19 Aug N component S component SW component NE component NW component SE component NW component SE component SW component NE component NW component SE component NE component SW component E component W component NW component SE component W component E component E component W component E component W component NE component SW component E component W component E component W component

17 TABLE 2 Continued IRAS Optical Position (J2000.0) Near-IR Position (J2000.0) BCL F SC R.A. Dec. R.A. Dec. R K (1) (2) (3) (4) (5) N component S component NE component SW component NE component SW component N component S component S component N component N component S component W component W component E component N component S component E component W component NW component SE component E component W component SE component NW component SE component NW component SW component NE component SW component NE component EE component EW component W component E component W component WW component N component S component

18 TABLE 2 Continued IRAS Optical Position (J2000.0) Near-IR Position (J2000.0) BCL F SC R.A. Dec. R.A. Dec. R K (1) (2) (3) (4) (5) NW component SE component W component E component E component W component S component N component W component E component W component E component N component S component E component EE component W component W component E component NE component SW component W component E component NW component SE component W component E component S component N component N component S component NW component SE component Col 1: IRAS name. The nomenclature follows that of Figure 1. Col 2: Optical position of the nucleus Col 3: Near-Infrared position of the nucleus Col 4: R-band bottom contour level in Fig. 1 in magnitudes arcsec 2 Col 5: K -band bottom contour level in Fig. 1 in magnitudes arcsec 2 3

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20 arxiv:astro-ph/ v2 19 Aug 2002 TABLE 3 R and K Photometry IRAS FSC R R 4 K K 4 R K (R K L(R) L(K ) ) 4 L(R 4 ) L(K 4 ) M R M R4 M K M K 4 (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) N component S component SW component NE component NW component SE component NW component SE component SW component NE component NW component SE component NE component SW component E component W component

21 TABLE 3 Continued IRAS FSC R R 4 K K 4 R K (R K L(R) L(K ) ) 4 L(R 4 ) L(K 4 ) M R M R4 M K M K 4 (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) N component S component W component E component E component W component E component W component NE component SW component E component W component W component E component N component S component N component S component NE component SW component

22 TABLE 3 Continued IRAS FSC R R 4 K K 4 R K (R K L(R) L(K ) ) 4 L(R 4 ) L(K 4 ) M R M R4 M K M K 4 (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) N component S component S component N component NE component N nucleus S nucleus SW component W component E component N component S component E component W component NW component SE component E component W component SE component NW component SE component NW component SW component NE component

23 TABLE 3 Continued IRAS FSC R R 4 K K 4 R K (R K L(R) L(K ) ) 4 L(R 4 ) L(K 4 ) M R M R4 M K M K 4 (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) SW component NE component E component EE nucleus EW nucleus W component E component W component WW component N component S component NW component SE component W component E component E component W component S component N component W component E component W component E component N component

24 TABLE 3 Continued IRAS FSC R R 4 K K 4 R K (R K L(R) L(K ) ) 4 L(R 4 ) L(K 4 ) M R M R4 M K M K 4 (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) S component E component NW nucleus SE nucleus W component W component E component NE component SW component W component E component NW component SE component W component E component S component N component N component S component NW component SE component Note: None of the photometric measurements has been corrected for Galactic extinction because b > 30 for these sources. Col 1: Object name. The nomenclature follows that of Figure 1. Col 2: Total R magnitude. Col 3: R magnitude within central 4 kpc diameter. Col 4: Total K magnitude. Col 5: K magnitude within central 4 kpc diameter. Col 6: Total R K. Col 7: R K within central 4 kpc diameter. Col 8: R Luminosity ratio of total to central 4 kpc diameter. Col 9: K Luminosity ratio of total to central 4 kpc diameter. Col 10: Absolute R magnitude. Col 11: Absolute R magnitude for central 4 kpc diameter. Col 12: Absolute K magnitude. Col 13: Absolute K magnitude for central 4 kpc diameter. 5